CBSE Class 11-science Answered
A police man is moving with constant speed on a straight road. When he is at a distance 250m behind a car, the car starts accelerating from rest and move with a constant acceleration 2m/s2. The minimum speed of the police man such that he can catch the car is
Asked by ragunive | 09 Aug, 2019, 08:37: AM
Expert Answer
Let t is the time duration taken by police to catch the thief.
If a is acceleration, then distance travelled by thief staring from rest = (1/2) a t2 = (1/2)×2×t2 = t2 ...............(1)
If v is uniform speed, then distance travelled by police = v×t ............................(2)
Since initially, Police is 200 m behind the thief, from eqn.(1) and (2), we get , v×t = t2 + 250 .....................(3)
Hence Eqn.(3) is written as quadratic form as, t2 - (v×t) +250 = 0 ...................(4)
Hence, t =(1/2) [ v± ( v2 - 1000 )1/2 ] .................. (5)
In eqn.(5), t is real only if v2 ≥ 1000 or minimum value of v is around 31.62 m/s
Answered by Thiyagarajan K | 09 Aug, 2019, 01:35: PM
CBSE 11-science - Physics
Asked by sheikhsaadat24 | 17 Apr, 2024, 09:41: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by sy123946 | 07 Apr, 2024, 04:23: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by derhebha955 | 03 Apr, 2024, 09:03: AM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by sumedhasingh238 | 29 Mar, 2024, 05:15: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by sumedhasingh238 | 28 Mar, 2024, 11:10: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by roshnibudhrani88 | 23 Mar, 2024, 05:52: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by emad.amd | 21 Mar, 2024, 12:00: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by vinitdubey7735 | 14 Mar, 2024, 11:21: AM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by om636694 | 04 Mar, 2024, 09:10: PM
ANSWERED BY EXPERTCBSE 11-science - Physics
Asked by rajuinwati12 | 04 Mar, 2024, 09:22: AM
ANSWERED BY EXPERT
